Relieving-lathe.



F. MULLER.

RELIEVING LATHE.

APPLICATION FILED DEC. 30, i916.

Patented Apr. 41, 1919. 5 SHEETS-SHEETI INVENTOR 4 Prim/f ller im wm,

F. MULLER.

RELIEVING LATHE.

APPLICATIGN FILED DEC. 30, |916.

Patented Apr. 1, 1919..

www?.

5 SHEETS*SHEET 2.

' @RNEY INVENTOR [Wieder/l1 Milf/er F. MLLER.

RELIEVING' LATHE.

APPLICATION FILED DEC- 30. 1916. 129,207. Patented Apr. 1, 19111.

"5 SHEETS-SHEET- 3- 84 l n n mvENToR ,FY/'aa'/lc/v M//er BY J I, 1 my l1GRNEY ,la MULLER. v RELlavlNG LATHE. NPPLICATHLN. F.ILE D DEC. 30. |916.

Patented Apr. 1, 1919.

6 ssHEUs-snsis. wf y INVENTOR Frieder/fab Mil/er BU/ ma@ rrr f EWEFRIEDERICH MLLER, OF HARTFORD, CONNECTICUT, ASSIGNOR TO PRATT @a WHITNEYCOMPANY, OF HARTFORD, CONNECTICUT, A CORPORATION OF NEW JERSEY.

BELIEVING-LATHE.

To all whom may concern.'

Be it known'that I, FRIEDERIGH MLLER, a citizen of the United States,residing at Hartford, in the county of Hartford' and State ofConnecticut, have invented certain new and useful Improvements inRelieving- Lathes, of which the following is a specification.

The invention relates particularly to lathes for relieving reamers,taps, milling cutters, counter bores and other metal Working cutters.However, the machine is not limited for use upon cutters of the kindsmentioned and can be used in-practically all cases in which relievingmovements of the cutting tool are required. For the sake of conveniencethe term cutters is used throughout this specification, but it will beunderstood that the term is intended to include not only rotary metalworking tools but also any other articles for which relief is required.

One of the objects of the invention is to provide an improved mechanismfor actuating the cutting tool to give the required relieving movementsthereto, the said mechanism preferably permitting easy adjustment of theextent of the said movements.

Another object of the invention is to provide automatic means wherebythe cutting tool can be fed, preferably intermittently, so as to take afresh chip at each revolution of the cutter; and, stated morespecifically, the said object of the invention is to provide anautomatic feeding mechanism having certain improved features whereby-therate of feed canbe adjusted, whereby the extent of feed can be limited,whereby preliminary adjustments of the tool can 'be readily effectedmanually, and wherebyA other novel and important results can be ac,-complished.

Another object of the invention is to provide in combination with tlieimproved tool actuating mechanism, or with `the improved feedingmechanism, or with both, a construction permitting the angularadjustment horizontally of the tool holding and supporting elementswhereby the angle of' approach of the tool to the cutter may bevaried asrequired.

A further object of the invention is to Aprovide in a machine of thecharacter set forth an improved mechanism for driving the live spindleand for supplying power to the devices which operate the cutting tool.

Specification of Letters atent.

Application filed December 30, 1916. Serial No. 139,838.

if l'l u A still further object o the invention is to provide in amachine of the character set forth, an improved tailstock and mountingtherefor, which permit the free movement of the cutting tool and itsholding and supporting elements. i

Additional objects will be apparent from the following specification andthe claims.

In the accompanying drawings I have shown in detail a machine embodyingthe invention, and in the following specification this machine will bedescribed in detail in order that one embodiment of the inventionmay beclearly understood. .I desire, however, to point out'that the inventioncan be embodied in other ways and that the said drawings and descriptionare to be understood merely -as illustrative and notas defining orlimiting the scope of the relied upon for that purpose. I desireparticularly to state that certain features of the invention can be usedwithout other features thereof and that for certain classes of work manyof the elements herein shown and described can be advantageouslyomitted.l I t will be understood that a machine thus modified orsimplified falls within the scope of this invention, particularly as setforth in certain of the claims.

Of the drawings:

Figure 1 is a side elevation, certain of the parts being shown insection.

Fig. 2 is a plan view. In this view the tool holder, the tailstock withits support and other parts are omitted for the sake of clearness.'l

Fig. 3 is a left end elevation.

Fig. 4 is a transverse sectional View taken along the line 4--4 of Fig.1.

Fig. 5 is a transverse sectional view taken along the line 55 of Fig. 2.

Fig. 6 is a longitudinalv sectional view of a spindle construction thatmay be used.

Fig. 7 is a fragmentary sectional view 100 vation, with parts insection, showing an 105 alternate form of feed mechanism.

Fig. 10 is a fragmentary front elevation, with parts in section, of themechanism shown in Fig. 9.

Referring lto the drawings, 1 represents 110 the main base or bedl uponwhich the other vcasting 4 rigidly secured to the bed. This casting isprovided with suitable bearings 5 and 6 in which there is rotatablymounted a live spindle 7, which preferably carries a center 8 and a faceplate 9.

llioosely mounted on the spindle 7 are two worm wheels 10 and l1.Preferably, .as indicated in Fig. 2, the teeth of the worm wheel 10 areadapted to mesh with a doublethreaded worm, and the teeth of the wormwheel 11 are adapted to mesh with a singlethreaded worm. Extendingtransversely of4 the headstock and mounted in suitable bearings'in thecasting 4, is a drive shaft 12 provided at its rear end with a drivingmeans, here shown in the form of'a setof cone belt pulleys l1?. Securedon the drive shaft 12, preferably adjacent the belt pulleys, is a pinion14 which meshes with pinions 15 and 16 mounted respectively on suitablymounted transverse shafts 17 and 18. Mounted respectively on the shafts17 and 18 are worms 19 and 20 which mesh respectively with the aforesaidworm wheels 10 and 11. When the worm wheels are constructed as alreadydescribed, the worm 19 is provided with double threads and the worm 20with a single thread. It will be seen that the construction is suolithat when the worms 19 and 2O are rotated the worm wheels will be givendifferent rotative speeds, the wheel 10 in this case having a speedconsiderably in excess of that of the wheel 11.

Splined to the spindle between the worm wheels 1() and 11 is a clutchelement 21 having teeth at each side adapted respectively to mesh withsimilar teeth formed on the worm wheels. lt will be seen that by meansof this clutch element 'either of the worm wheels can be operativelyconnected with the spindle.

For moving the clutch element 21 longitudinally of the spindle, there isprovided an oscillatory lever 22 provided with pins or projections 23,fitting in a circumferential groove in the clutch element. The lever 22is secured to a transverse rock shaft 24 provided vvith' an operatinglever 25. lt will be seen that by means of the lever 25 the clutchelement 21 can be controlled so as to be maintained in neutral positionas shown in Fig. l, or moved into engagen'lent with either of the wormwheels 10 or 11. The lever 25 raeaaor 4 and thus lock the lever and theclutch element in the desired position.

The ta-ilstock 3 is so mounted that it does not interfere in any waywith the operation.

of the reciprocating tool carrying slide which will be described indetail hereinafter.

'As illustrated, there is provided a horizontal supporting bar 27 whichis parallel with the bed 1. Preferably, this bar is supported at bothends, the support at the headstock end being in the form of a casting 28which is secured to the headstock casting 4 by suitable means such asthe bolts 29, 29. 'lihe casting 28 is provided with a Cap plate 30 heldin place by screws 30a. At the other end the bar 27 is supported by abracket 31 which rests upon and is secured to the rear part of the bedl. The bracket 31 is provided with a cap plate 32 suitably held in placeby screws similar to the screws 80a. Preferably the bracket 31 engagesthe usual ways with which'the bed is provided, ,and is ad justable alongthese ways so as to provide asupport for the bar 27 as close to thesupport 28 as the circumstances at any given time permit.. A bolt 33together with a cross' bar 33 provide convenient means for clamp-` ingthe bracket 31 in its adjusted position. 95

Preferably the bar 27 is detachably engaged with its supports, beingnormally held against movement by set screws 34, 34 and e5, 35.

The bar 27 is referably hollow and polygonal in form, being shown astriangular. rllhe triangular form is particularly advantageous as itpermits the supports for the bracket to be provided with lll-shapedopeningsinto which the bar fits without any possibility of looseness.The pressure applied to the top of the bar by means of the said setscrews 34, 34 and 35, 35, forces the sides of the bar into firmengagement with the walls of the openings in the supports. Preferablythe central portions of all three sides of the bar are depressed so asto provide 'bearing surfaces only near the corners thereof. l Anotheradvantage of the triangular construction is that it provides a minimuminterference with light.

The tailstock comprises a main frame in the form of two castings 36 and37 formed to fit together and closely engage the surfaces ofthe bar 27.These castings are suitably connected at the top by screws 38. 38 and atthe bottom by screws or bolts 39,/ 39. There is also provided a bolt 40by means of which the two sections can be clamped firmlv against thesurfaces of the bar. The lower parts o f the castings 36 and 37 arerecessed to receive a longitudinally slidable sleeve 4l in which ismounted a center 42. The sleeve 41 can he moved longitudinally bv meansof the screw 43 controlled by the hand wheel 44.l By means of thevcla-mp 45 controlled by the screw 46 and handle 47, kthe sleeve 4l z canbe clamped in ladjusted position.

lt will be seen that by suitably position ing the tailstock on the bar27 and by then adjusting the center 42 by means of the sleeve 4l and thehand wheel 44, a cutter or other article to be relieved can be securedin the usual way between the two cen ters 8 and 42; andthe cutter can beconnected to the face plate on the live spindle in any usual orpreferred way to be rotated.

Asalready stated, it may in some cases be preferable to mount the cutterentirely on the live spindle, and for this purpose a collet mechanismsuch as shown in Fig. 6 may be provided. The spindle 7 is hollow androtatably mounted therein is a sleeve or bushing48 controlled by a handwheel 49. The sleeve 48 has threaded engagement with a collet 50. Byturning the hand wheel and the sleeve in one direction the collet can bedrawn inward and closed or moved outward and permitted to open. Theshank of a cut-4 shown in Figs. 1'and4 it can be held by a colletmechanism" such as that described.

When the cutter is supported entirely on the live spindle it may bedesirable for the sake of convenience to entirely removeI the -tailstockand its supporting means. This can be easily'done by loosening the bolt33 and the bolts 29, thus making it possible to detach as a unit thetailstock, the supporting bar and the two castings in which the bar ismounted.

The cutting tool must be so held and sup ported that iti-can be movedtoward and from the cutter to be relieved in timed relation to therotation thereof. The tool must make ,as many movements forward andbackward during each rotation as the l cutter has teeth. A cutting toolis indicated at 52, and forsupporting it there is provided areciprocable horizontal slide a53 to which the tooll is secured in anysuitable way. A supporting device 54 is provided for the slide 53 andpreferably this supporting device is provided with separated parallelways with which the slide engages. l7l/'hen it is desired to make itpossible for the cutting tool to approach the cutter from any angle, thesupporting device 54 must be in the form of a turntable rotatable abouta vertical axis, and in the drawings the supporting device 54 is soshown. The' turntable 5.4 rests upon a saddlel 55 which is supported onthe bed of the machine. The turntable is provided with annular bearingsurfaces which fit similar bearing surfaces formed on the saddle, andthe saddle is also'provided with an annular T- slot 56 into which extendT-bolts 57 adapted to lock the turntable in any desired angu.

lar position. Preferably the saddle 55 is slidable along the bed l, thebed being provided with the usual ways on which the saddle rests. Bymeans of suitable bolts 58 the saddle can be clamped in any desiredposition. Pivoted at 59 on'the supporting device or turntable 54 is alever 60 having two 'lev arms, one of which has connection with theslide 53 and the other of which is engaged byia suitable cam 6l. When`the .supporting device 54 is in the form of a turntable, as here shown,the cam 61 is positioned centrally with its axis coincident with theaxis of the turntable, thus making it possible for the cam and lever toproperly coperate with the turntable in any position of adjustment.Preferably the canil is in the form'of a groove in the top of a wheel62. The wheel 62 is mounted on a conical stud 63 secured to adepresse'dpart of the sad dle 55. The wheel 62 is preferablyprovidedwith'worm teeth 64 which mesh with a worm 6.5 on a shaft 66. When thesaddle 55 is adapted for longitudinal movement along the bed, the shaft66 is longitudinally arranged and the Worm 65 is splined to it. lt willbe clear that when the shaft 66 is rotated motion will be transmittedthrough the worm and worm wheel to rotate the cam.

Une arm of the lever 60'is provided with a roller 67 which extends intothe ca-m `groove 61. The groove is' preferably of the form shown in Fig.2, being adapted to move the lever slowly in one direction and rapidlyin the other.v Connected with the slide 53 for normal movement in unisontherewith, is a device 68 to which power is applied by the-lever foractuating the slide.

The lever 60 is adjustable so as to vary the amount of movement which ittransmits to the device 68 and to the tool-carrying slide Preferablythis adjustment is effected by changing the ed'ective length of one armof the lever and as shown, this arm of the lever is constructed with twotelescopically engaging parts. At the sides of the body part of thelever are -two slidable plates 69, 69 formed with oppositely disposedthickened portions 70, 70, each with a surface in the form of a sectionof a cylinder, these two cylindrical surfaces having a common center. The surfaces of the enlargements 70, 76 fitbetween transveise parallelsurfaces 7l. 71, provided on the actuating device 69, and as thesurfaces on the parts 70. 7 O are cylindrical, the engagement with thesurfaces 7l, 7l is maintained notwithstanding any angular movement. Thetwo plates 69. 69 are secured to a block 72 which is centrally rccessedto receive an extension 73 on the body part of the lever. An adjustingscrew 74 extends through an aperture in the block and is held againstlongitudinal movement with respect thereto. The inner end of the screwextends into a threaded aperture in the said extension 73. The outer endof the screw is squared to receive a wrench, and by turning the screwthe block 72 together with the plates 69, 69 can be moved so as to bringthe center of the cylindrical surfaces 70, 70 toward or away from thepivotal center of the lever. Preferably at the extreme inner positionthe center of the cylindrical surfaces coincides with the pivot-alcenter, and no movement of the actuating device or the -slide takesplace as theV lever is oscillated.

' As the screw is turned to move the center of the cylindricial surfacesoutward, the movement of the actuating device and slide is graduallystarted and this movement is increased as the effective length of thelever is increased. In this way the extent of movement of the tool slidecan be varied from zero to maximum. The screw 74 can be clamped by meansof the screw 7 5.

As already stated, the cam 61 is in the form of a groove, thus making itpossible for the cam to positively move the lever in each direction, theconstruction being distinguished in this respect from otherconstructions in which the cam is elfective in one direction only,reliance being placed upon a spring for eecting movement in the otherdirection. While, as stated, the cam acts positively in both directions,I nevertheless prefer to provide a spring for assisting the cam ineffecting the short rapid return movement of the slide. By means of thespring I avoid excessive strain on the lever, the cam, and the severalpower transmitting parts. As illustrated, the turntable 54 is providedwith an aperture 76 parallel with the line of movement of the actuatingdevice and slide, and. a spring 78 is provided which abuts at one endagainst the actuating device 68 and at the other end against a plug 79threaded into the aperture 76. For holding the spring 78 in place thereare provided pins 77 and 7 7 secured respectively to the actuatingdevice 68 and to the plug 79.

I have shown the two arms of the lever 60 as extending at right anglesto each other as this construction is preferable for a machine of thetype here illustrated. It will be understood. however, that under somecircumstances, this right-angled construction need not be used.

As already stated, the cam wheel 6:2 is rotated by means of the shaft 66and the worm 65. For rotating the shaft 66 I preferably provide thefollowing mechanism. A transverse shaft 80 is mounted in suitablebearings in the bed. and this shaft carries a bevel gear 8l which mesheswith a bevel gear 82 on the shaft 66. Power to rota-te the shaft 8O istransmitted from the aforesaid drive shaft 12 by means of a series ofgears, these gears being interc-hangeable so as to provide for thedriving of the shaft 80 at diifercnt speeds. As shown. the shaft 12 isprovided at its forward end with a pinion 83 which meshes with a gear84: carried by a shaft 85 mounted in the headstock casting. Itigidlyconnected with the gear 84C is a pinion 86 which meshes with an idlergear 87 mounted on a stud 88 which is slidable in a bracket 89 securedto the bed. This gear 87 meshes with ya second idler gear 90 which ismounted on a stud secured to a bracket 91 mounted for swinging movementon the shaft 80. This bracket can be locked by means of a bolt 92. Thegear 90 meshes with a gea-r 93 on the shaft 80. It will be seen thatwhen the shaft 12 is rotated the shaft 80 will also be rotated but at a.greatly reduced speed. If a dilferent speed is required for the shaft80, this can be obtained by removing the gears 8.3, 84: and 86 andsubstituting gears of different diameters. It will be noted that theidler gears 87 and 90 are adjustable so that proper meshing with the.differently diametered gears is effected.

As has already been stated, it is necessary for the cutting tool to makeone forward and backward movement for each tooth of the cutter to berelieved. It is therefore necessary that for each revolution of the livespindle the cam 6l be'given as many rotations as the cutter has teeth.By using gears of the proper sizes the number of roice tations of thecam for each rotation of the live spindle can be varied, and a furthervariation can be obtained by connecting one or the. other of the wormwheels 10 or 11 with the live spindle, thus varying the speed of thespindle with respect toit-he speed of the drive shaft 12. By means ofthis twospeed worm and wheel drive mechanism for the spindle. I amenabled to greatly increase the range of the machine without providingan unduly large number of interchangeable gears.

As already stated, the carriage is preferably movable longitudinally ofthe bed and this movement can be effected either manually or by power.For the purpose of moving the carriage manually there is provided a rack94: secured to the bed. Connected with the saddle 55 is the apron 95 onwhich is mounted a short transverse shaft carrying a pinion 96 meshingwith the rack. By means of a hand wheel 97 the pinion can be turned tomove the carriage.

Mounted in suitable bearings at the rear of the machine is a lead screw98 adapted to be connected with the live spindle by means of suitablegearing. This gearing of itself constitutes no part of my presentinvention and can be of any usual or preferred form.

p the spindle 7 and 'adapted to mesh either with a gear 10001l an idlerpinion 101. The gear 100 and the idler pinion 101 are mounted on aswinging bracket 102 adapted to be controlled by the link 103 and thehand lever 104. bracket 102 can be moved either to bring the gear 100into meshwith the gear 99 as shown in' 'Fig 3- or to bring the idlerpinion 101 intoimesh with the gear, or to bring" both the gear 'and thepinion out of mesh. vFrom the gear-100 power is transmitted -to the leadscrew through the gears 105, 106, 107 and 108, someof which areinterchangeabley in the usual way to vary the rateof rotation of thelead screw with rection. which is connectible with the carriage by meansof the screw 110. When the'screw is respect to that of the spindle. Itwill be seen that the lead screw can be entirely disconnected from thespindle or can be con- 20 nected therewith for rotation `in either di-109 is a nut on the lead screw not in luse the nutl will ordinarily bedisconnected from the carriage so as to permit l the movement of thecarriage manually.

As already stated, the cutting tool 52 canbe mounted on theslide 53 in`any suitable manner. However, when the slide is mount-4 ed asherein'shown and described, I prefer a.

tool holding and vsupporting means which comprises a plate 111ad]ustable angularly with respect to the slide and alsolongitudinally'of the slide. The plate 111 is connected with aplate 112having an annular beveled surface. A; ring113 having a similar beveledsurface surrounds the plate 112 i 'and is adjustably secured to theslide by means of bolts 114 engaging T-slots 115. This constructionpermits the plate 111 to be moved' longitudinally of the slide orangularly, and when the bolts 114 are tightened the plate is locked inplace. Mounted on the plate 111'is a slide 116 horizontally movableunder the control of a screw '117.

' -Mounted on the slide is a clamp 118 in which v vmay be held the tool52.

'- to takea fresh chip at each rotation of the.

. Means are provided wherebyI the lextent of the forwardmovementsorf-the cutting tool 'may be increased' as the tool'.rotates,j

'thus effecting lfeeding and causing the tool l cut-ter. I preferV to:effect the feedingautom'aticallyand preferably the construction l issuch that the feeding takesplaee' intermittently lat the end of eachrotation ofthe The actuating device 68has been described i as normallymovable in .unison with lthe tool carrying slide 53. The two elementsare connected by a rotatable screw 11S-which has threaded engagementwith the'fslide.

aperture in 'the' actuating device and is held against longitudinalmovement with respect By means of this lever the A this pawl the ratchetwheel is rotated in the The inner end of the screw extends through an.

to the said device byrmeans of lock nuts at' 119. Mounted in the devicewhich su ports the slide 53 (in this case the turntab e 54)'` is a-shortrotatable shaft 120 vprovided' at its inner end with a clutch element121 which is shaped to engage the end of, theA clutch element 122 on thescrew- 1'185 and impart' rotary'movement thereto. It willdisk and theWorm Wheel iS, a 'frictionf washer. Springs .are provided for clsiil'gvfrictional engagement at vthe'washe'r, hns providing a frictionalconnection bei n the worm wheel and the shaft.

The devices for rotating the wo may vary with thel type-of machine, butIn a machine of the sort illustrated, in whichgthe slide 53 -is mountedon a turntablathef" lowing elements are preferably providedfforoperating the worm. Asshown in Fig' the Worm 124 is secured to vahorizontal s v 126 mounted in suitable bearings in the turn-. table 54.'-At oneend of the shaft 126 is 'a j bevel gear 127 meshing with abevel'pinion 100 128v secured to a vertical bushing 129. This lbushingcarries at its lower end a toothed yclutch element 130 upon'which isrotatably i. ,I mounteda gear 131. Slidably. and rotatan 1105 blymounted in the bushing 129is a shaft 132 to the lower end of which issecured a ratchet wheel A133 having on its upper sur'- face teethadapted to mesh with the teeth of i the clutch element 130. At theupper` end 0f I l@ the shaft 132-'is a grooved collar 134 into thegroove of which iit projectionson the forked arm of a bell-crank '135.By moving the lbell-crank the shaft 132 can be raised or low# 4- ered tobring the clutch teeth o n the ratchet wheel 133 into or out .ofengagement with 115 the teeth on the clutch element 130. Mount ed on thegear 131 is a ratchet or pawl 136 springl pressed. into engagement withthe teeth of the ratchet wheel 133. By means of clockwise directionwhenever the gear is rotat'ed in the said direction, and this motion istransmitted to the sleeve 129 and the parts connected therewith wheneverthe ratchet wheel is in itsupper position tov engage the clutch teeth.

Mounted on the turntable 54 for move? ment about the axis thereof, is asuitable power transmitting element, and by preference this element isin the forni of 130 aft' an annu-lar toothed ring 137. As shown, thering 137 is mounted in an annular rabbet formed at the periphery of theturntable, the bottom of the ring engaging the top surface of the saddle55. The ring is provided with teeth on its outer periphery, and theconstruction of the turntable is such that these teeth are exposedthroughout the major portion of the periphery. Means are rovided forimparting movement to the ring 137, and this movement is transmitted tothe gear Wheel 131 by means of idler gears 138 and 139 mounted on theturntable. Inasmuch as the ring is concentrically mounted, the powerconnection with the said gear 131 is maintained for all positions of theturntable. For imparting movement to the ring 137 there is preferablyprovided a gear wheel 140 meshing with the teeth of the ring. This gearWheel is secured to a vertical shaft 141 mounted in the saddle 55, andat the lower end of the shaft is a bevel pinion 142 meshing with a bevelgear 143 mounted on a longitudinal shaft 144. l/Vhen the saddle islongitudinally movable as herein shown and described, the gear 143 issplined to its shaft to permit longitudinal movement thereon.

The shaft 144 is mounted in suitable bearings in the bed' and isprovided at one end with means for imparting movement thereto.Preferably the shaft is given an oscillatory movement and the means forimparting such movement as shown, comprises a pinion 145 meshing with arack 146 secured to or formed on a link 147. Loosely mounted on theshaft 145 is a housing 148 which serves as a guide for the rack, holdingit in mesh with the pinion. Pivotally mounted on the head-stock castingis a bell-crank 149, one arm of which is provided With a T-slot. AT-bolt 150 fits in the T-slot and serves as apivot for the upper end ofthe rod 137. This pivot is adjustable along the arm and the amount oftravel of the link as the bellcrank is oscillated can be varied fromZero to maximum. Mounted on the live spindle 7 is a disk 151 providedWith a cam groove 152. A roller on the bell-crank 149 fits this grooveand the groove is so shaped 'that in at least one direction thebell-crank is given a rapid movement.

From the foregoing description it Will be seen that as the live spindleis rotated the cam 152 imparts a rocking movement to the bell-crank 149,which serves to reciprocate to a greater or less extent the link 147 andthe rack 146. By means of the rack, oscillatory movement is transmittedto the shaft 144 and through the connections described, this movement istransmitted to the gear 131. By means of the paWl 136 the movement ofthe gear 131 in one direction is transmitted to the ratchet Wheel 133.the pawl passing freely over the teeth of the ratchet Wheel When thegear 131 movesI in the other direction. Then the ratchet wheel. isconnected with the sleeve 129 the intermittent movement thereof istransmitted to the worm Wheel 123 from which, by 'means of the frictiondevices described, it is transmitted to the shaft 120 and the feed screw118. As the movement in one direction oecurs once for each revolution ofthe spindle and of the cutter driven thereby, the feed is effected oncefor each revolution of the cutter. The amount of feed at each revolutioncan be varied by adjusting the pivot at 150.

In addition to the automatic feeding means, I preferably also providehand operated means for controlling the tool. As illustrated, this handcontrolled means comprises a hand Wheel 153 mounted on a short shaft 154on which is mounted a spiral gear 155 meshing With a spiral gear 156 onthe shaft 126. Frequently in order to start the cutting it is desirableto advance the tool in the feeding direction at a speed greater than.that caused by the automatic mechanisln. This can be done at any time bymeans of" the hand wheel Without interfering in any Way with thekoperative relation of the automatic mechanism. The ratchet Wheel isadvanced With respect to its driving pawl, the teeth of the Wheel freelyslipping under the paWl. Whenever the more rapid manual movement isdiscontinued` the movement by means of the pavvl is resumed as before.In case it is desired to move the tool backward the ratchet Wheel isdisconnected by means of the bell-crank 135, thus placing the toolentirely under the control of the hand Wheel.

For automatic feeding it is preferable to provide means whereby thefeeding is automatically stopped at a predetermined limit. I provide alimiting or stopping device Which comprises a button 157 on a T- boltsituated in a T-slot 158 in the disk 125. Coperating With the button 157is a movable stop 159 which in operative position is adapted to beengaged by the button as the disk 125 rotates. By suitably adjusting thebutton with respect to the disk the button can be made to engage thestop after feeding has taken place to the desired extent. It will beseen that as soon as the button does engage the stop, further movementof the shaft 120 and of the feed screw is prevented, the frictionelements permitting the worm to continue to turn as before.

When the tool is to be controlled manually, it is desirable to preventthe engagement of the button157 and the stop 159,-and

a cam 162 which engages the lower forked end of the bell-crank 135. Theshaft 160 is also provided with a cam 163 which is adapted to engage theend of the stop 159 to hold it in operative position, the cam opposing aspring tending to move the stop out of operative position. The two cams162 and 163 are secured to the shaft in such relation to each other thatwhen the handle 161 is moved in one direction the stop 159 is moved intooperative position and the ratchet wheel 131 is connected with theclutch element 130. When the handle 161 is moved in the other directionthe stop'159 is permitted to be withdrawn and the ratchet wheel isdisconnected, thus leaving the tool controlling mechanism entirely freefor manual operation.

In addition to forming part of the automatic stop mechanism the frictionelements described also serve to prevent injury to the machine in casethe normal feeding operation is interfered with in any wav. In the caseof any abnormal resistance to feeding, the friction elements will slipand no harm will result.

In operation, the operator first observes the number of teeth on thecutter to be relieved and then by placing the lever 25 into properposition and by making use of the proper gears 83, 84 and 86 he prqvidesfor the movement of the tool slide as many times per revolution of thespindle as the cutter has teeth. .It will be understood that theprovision of the two diierently speeded connections from the drive shaft4to 'the spindle makes it possible for the same set of change gears 83,84 and 86 to be, used for cutters with two different numbers of teeth.This construction therefore makes it possible to use the machine for therequired range of tooth numbers with a much smaller number of changegears than would otherwise be necessary. By adjusting the lever` 60 bymeans of the screw 74 the amount of movement of the slide is regulatedin accordance with the amount of relief desired on each tooth of thecutter. By adjusting the pivot bolt 150 in its slot the rate of feed isregulated as required. The cutter to be relieved is put in place andsecured in the usual way,

and if necessary the turntable is moved so as to bring the line ofmovement of the tool slide at right angles to the faces of the cuttingteeth. It will be understood that the turntable is movable through anangle'of 180O or more so that cutters of any sort can be relieved. Oneofthe possible positions of the turntable is indicated by dotted lines .inFig. 2. The mounting of the tailstock on an overhead support permits theturntable and the tool slide and the parts Ycarried thereby, to movefreely under it without interference of any sort. When the parts havebeen 'ed thereon.l -Splined to the element 130a controlled by, a lever1353, this lproperly adjusted as outlined above, the tool is broughtinto working relation with the cutter, being advanced manually ifnecessary. The limit button 157 is so adjusted as to stop the feed aftera sufscrew can be used to feed the carriage longitudinally so that thecutting tool will traverse the entire length of the cutter. It will beunderstood that ordinarily when the lead screw is in use the automaticfeed will be disconnected. n

It will be seen that the action of the machine is entirely automaticafter the preliminary adjustments have been made and after the cutterhas been put in place, and no harm can result even if lthe machine doesnot receive the undivided attention of the operator as the feeding isautomatically stopped at the proper time, thus preventing any injury tothe cutter.

In Figs. 9 and 10 I have shown an alternate form of feed mechanism whichcan be substituted for the feed mechanism already described. Thismechanism is particularly adapted for use when lit is permissible toeffect the feeding gradually instead of intermittently at eachrevolution.

In Figs. 9 and 10 the shaft 126 is eXtendl ed and a ratchet wheel 133ais loosely mountshaft is a clutch lever being similar in function to thebellcrank 135 already described, being similarly actuated by the shaft160 and the cam 162A. The clutch element 130a is provided with teethadapted to engage similar teeth on the hub of the ratchet wheel 1331.The cam 162a is so positioned on the shaft 1 60'that when the stop 159is in operative position as shown, the clutch element 13Ga is held inengagement with the clutch teeth on the ratchet wheel. When the handlever 161 is moved to permit the withdrawal of the stop the clutchelement is moved to disengage the ratchet wheel. 1

Mounted o'n the turntable for movement about the axis of the shaft 126is a lever 164, this lever carrying'a pawl 136a which' normally engageslthe teeth of the ratchet wheel 1333. Foractuating the 'lever 164 to movethe pawl inthe operative direction,

thereV is provided a rod 165 slidably mounted in suitable brackets Oneend of the rod engages'the lever 164: and the other end of the rod ispositioned to be 'engaged by the block 72 forming a part of the lever60. A spring 167 engages the lever 164, thus tending to `anism lastvdescribed the feeding is e sive tooth of the cutter.

move the lever and the rod 165 toward the lever 60.

As the lever 60 with-the block 72 is oscillated the rod 165 `isreciprocated, this causing oscillation of the levei` 164. By means ofthepawl 136a the ratchet wheel 133a is rotated and feedi is effected in theway already described. ounted on the rod 165 is a'stop 168 ajustablyheld in position by means of a set screw. By means of the stop themovement right as view ed'in Fig. 9 can be limited, and in this way theextent of reciprocation can be varied and the rate of feed varied.`

It will be understood that withthe mechected at a substantially uniformrate, the cutting tool 'being advanced slightly at each succes- Inpractice the thickness of the chip will be successively increased ateach vtooth until one complete revolution of the cutter has been made,and the feed must be so adjusted as to provide the desired maximumthickness of chip at .the end of one revolution.

4 -After the first revolution chips ofvuniform thickness are removedfrom the succes-` sive teeth until the feeding is stopped, and

then the cutter mustbe rotated for. at least' one additional rotation invorder .to true-the teeth and bring their cutting edges at unil n formdistance from the axis.

driving cam 151 and all of the Itwill be'understood that when thefeeding mechanism shown in Figs. 9 and 10 is used, the major portion ofthe feeding mech- ',anism' shown in the otherligures is omitted.

In other words, it is possible to omit the arts driven therebyup'to theshat126 which is' driven by the ratchet wheel 133a as already de-SC-l'lbed. I i

What I claim is:- 4

-1. In a relieving lathe, the combination .of means for holding androtating a cutter, a tool holder, means comprisingy a singlethrowcamacting positively to advancethe tool holder slowly' toward the cutterand to withdraw it rapidly rotation of the cutter, and means for varyingfrom zero to maximum the extent o advance and withdrawal. a

2.' In a relieving lathe, the combination of means for holding-androtating a cutter, a-

means comprising a cam acting l positively to advance vthe tool holderslow-ly" toward the cutter and acting positively to tool holder,

withdraw it rapidly therefrom in timed 66 lation to the rotationthereof, and a spring p Y ab cooperating with the cani to assist ininoving` the tool holder away from the cutter.

3. In a relieving lathe,the combination of means for holding androtating a cutter, a tool holder, means for positively moving the toolholder toward and away from the cutoiv the rod toward the ter in .timedrelation to the rotation thereof, the said means comprising anoseillatinglever having two telescopically engaging parts,l and meansfor moving one o' ,the lever parts relatively to the other to change`the eiective length of the 'lever thereby varyingthe extent of movementof the tool holder.

4. In a relieving lathe, the combination of means for holding androtating a cutter,

a tool holding device provided with a slotA lel slot walls, and meansfor moving the last said lever part relatively to the other to changethe effective length of the lever thereby varying the extent of movementof th tool holding device.

5. In a relieving lathe, the combination of means 'for `holding androtating a cutter,

a tool holdingl device provided with a slot having parallel walls, meansfor moving the tool hlding'device toward and awayi'ronil the cutter -intimed relation to the rotation thereof, the said means comprising anoscillating lever having two telescopically engaging parts one o surfacefitting between and engaging the parallel slot walls, .and means formoving the 'last said lever part relatively to the other to bring theaxis of the cylindrical surface whichhas a cylindrical into or out ofcoincidence with the pivotal axis of the lever. l

6. In a relieving lathe, the combination j 5, l

of means for holding and rotating a cutter, 'a tool holdingv meanscomprising a horizontal turntable and a horizontal slide on theturntable, a cam mounted coaxially with the ti1rntableand rotatable intimed relation with the rotation of the cutter, and cam aciit tuatedmeans operable'for all positions of i' the turntable for moving theslide toward 4and away rointhe cutter, the said means being constructedtoact positively in leach direction. l. l

7. In a relieviv g lathe, the combination of 'means for holdingandrotating a cutter, a tool holding means comprising a horizontal.turntable and a horizontal, slide on the turntable, a lcam mounted..co'axially vwith the h" therotation of the`-cutter, cam actuated l cvfor moving tli'efzlide'toward and away the cutter, andmeansfor'varyingvthe extent of slidel movement.

8. In a relieving lathe, the combination of turntable and rotatable inltimed relation operable for-gllgfpositions of the turntable, a cammounted coaxially with the turntable and rotatable in timed relationwith the rotation of the cutter, cam actuated means operable for allpositions of the turntable for moving the slide toward and away from thecutter, and means operable while the slide is in motion for adjustingthe moving means and automatically locking it vin adjusted positionthereby varying the-extent .of slide movement.

9. In a relieving lathe, the combination of means for holding androtating a cutter, a tool holding means comprising a. horizontalturntable and a horizontal slide on the turntable, a cam mountedcoaxially with the turntable and rotatable in timed relation with therotation of the cutter, and means for moving the slide toward and awayfrom the cutter comprising a cam actuated lever pivoted on theturntable.

l0., In a relieving lathe, the combination of means for holding androtating a cutter, a tool holding means comprising ahorizontal turntableand a horizontal slide on the turntable, a cam mounted coaxially withthe turntable and rotatable in timed relation with the rotation of thecutter, and means for moving the slide toward and away from the cuttercomprising a cam actuated bellcrank lever operable for all positions ofthe turntable. j

l1. In a relieving lathe, the Combination of means for holding androtating a cutter, a tool holding means comprising a horizontalturntable and a horizontal slide on tle turntable, a cam mountedcoaXially with the turntable and rotatable in timed relation with therotation of the cutter, a cam actuated lever for moving the slide towardand away from the cutter, and means for adjusting the lever to vary theextent of slide movement.

12. In a relieving lathe., the combination of means for holding androtating a cutter, a tool holding means comprising a horizontalturntable and a horizontal slide on the turntable, a cam mountedcoaxially with the turntable and rotatable in timed relation with therotation of the cutter, a cam actuated lever for moving the slide towardand away from the cutter, and means for chang- 'ing the etlective lengthof the lever and thereby varying the extent of slide move-I ment. I

13. In a relieving lathe, the combination of means for holding androtating a cutter,

a tool liolding means comprising a horizontal turntable and a horizontalslide on the turntable provided with a slot having" the other to bringthe center of the cylindricalsurface into or out of coincidence with thepivotal axis of the lever, .and means for of means for holding androtating a cutter,

a tool holding means comprising a horizontal turntable and a horizontalslide on the turntable, a rotatable cam, a conical bearing stud for thecam rigidly mounted coaxially with the turntable, and cam actuated meansoperable for all positions of the turntable for moving the slide towardand away from the cutter in timed relation to the rotation thereof.

'16. In a relieving lathe, the combination oi means for holding and--rotating a cutter, a longitudinally movable tool carriage compri-singa horizontal turntable and a horizontal slide onl the turntable, andmeans operable for all positions of the turntable for moving the slidetoward and away from the cutter in timed relation to the rotationthereof, the said means comprising a unitary worm wheel and cam mountedcoaxially lwith the turntable, a worm engaging the worm wheel and alongitudinal shaft upon which the worm is splined.

17. In a relieving lathe, the combination or" means for holding androtating a cutter,

' a tool holder', a horizontal slide carrying the of means forholdingand rotating a cutter, a horizontal tool carrying slide, a slideactuating device' normally movable therewith,y `means engaging theslideand the actuating device for relatively adjusting them, areciprocating means engaging the actuating device, and means fixedagainst bodily movement with the slide for operating the said adjustingmeans while the slide is in motion. 19, In a relieving lathe, thecombination of means for holding and rotating a cutter,

a horizontal tool carrying slide, a slide actuating device normallymovable therewith, a screw extending longitudinally of the slide and theactuating device for relatively adjusting them, a reciprocating meansengaging the actuating device, and means iixed against bodily movementwith the slide and having slidable engagement with the screw foroperating it while the slide is in motion.

20. In a relieving lathe,the combination of means for/holding androtating a cutter, a tool holder, means for moving the tool holdertoward and away from the cutter in timed relation to the rotationthereof and independently of any movement of the tool along the face. ofthe cutter, and automatic means operable in timed relation with thecutter rotation for causing the forward limit of the movements towardthe cutter to be intermittently advanced.

V21. In a relieving lathe, the combination of means for holding androtating a cutter, a tool holder, means for moving the tool holdertoward and away from the cutter in timed relation tothe rotation thereofand independently of any movement of the tool along the face of thecutter, automatic means 'operable in timed relation with the -cutterrotation for causing the forward limit the cutter to be the rate ofmove-v of the movements toward advanced, and means for varying ofladvance of the forlard limit ments. j

2Q. In a relieving lathe, the combination of means for holding androtating a cutter, a tool holder, means for moving the tool holdertoward and away from the cutter in timed relation to the rotationthereof and independently of any Vmovement of the tool along the face ofthe cutter, automatic means operable in timed relation with the cutterrotation for causing the forward limit of the movements toward thecutter to be intermittently advanced, and means for varying the rate ofadvance of the forward limit of movements.

23. In a relieving lathe, the combination of means for holding androtating a cutter, a tool "holder, means for holder toward and away fromthe cutter in timed relation to the rotation thereof and independentlyof any movement -of the tool along the face of the cutter, and anintermittently' acting automatic feeding means operable in timedrelation with the cutter rotation for the tool holder supplemental tothe said moving means.

F24. In a relieving iathe, the combination of means for holding androtating a cutter, a tool holder. means for moving the tool holdertoward and away from the cutter in timed relation to the rotationthereof and independently of any movement of the tool along the faceofthe cutter, automatic. feeding means operable in timed relation withthe moving the tool` a tool holder.

cutter rotation for the tool holder supple mental to the said movingmeans, and means for adjusting the feeding means to vary the rate offeed.

25. In a relieving lathe, the combination of means for holding androtating a cutter, a tool holder, means for moving the tool holdertoward and away from the cutter in timed relation to the rotationthereof and independently of any movement of the tool along the face ofthe cutter, an intermittently acting automatic feeding means operable intimed relation with the cutter rotation for the tool holder supplementalto the said moving means, and means for adjusting the feeding means tovary the rate of feed.

26. In a relieving lathe, the combination of means for holding androtating a cutter, a horizontal tool carrying slide, a slide actuatingdevice normally movable therewith, means engaging the slide and theactuating device for relatively adjusting them, a reciprocating meansengaging the actuating device and automatic means connected with thesaid adjusting means for operating it.

27. In a relieving lathe, the combination of means for holding androtating a cutter, a tool holder, means for moving the tool holdertoward and away from the cutter in timed relation to the rotationthereof, and means for intermittently giving the tool holder a feedingmovement supplemental to the aforesaid normal movements, the said meanscomprising a cam rotatable in timed relation to the rotation of thecutter.

28. In a relieving lathe, the combination of means for holding androtating a cutter, a tool holder, means for movingY the tool holdertoward and away from the cutter in timed relation to the rotationthereof, and mechanism comprising a cam rotatable in timedrelation tothe rotation of the cutter for intermittently giving the tool holder afeeding movement supplemental to the aforesaid normal movements, andmeans for varying the citent of feeding at each cam actuation.

29. In a relieving lathe, the combination of means for holding androtating a cutter, means for moving the tool holder toward and away fromthe cutter in timed relation to the rotation thereof. a device forgiving the tool holder a feeding movement supplemental to the aforesaidnormal movements. and automatic frictionally acting means for` operatingthe feeding device.

30. In a relieving lathe, the combination of means for holding androtating a cutter, a tool holder means for moving the tool holder towardand away from the cutter in timed relation to the rotation thereof, adevice for giving the tool holder a feeding movement supplemental to theaforesaid normal movements, automatic means for operating the feedingdevice, and means for preventing the operation of the feeding device bythe said. automatic means after feeding has taken place to apredetermined extent.

3l. In a relieving lathe, the combination of means for holding androtating a-cutter, a tool holder, means for moving the tool holder`toward and away from the cutter in timed relation tothe rotationthereof. a device for giving the tool holder a feedingmovementsupplementa-l'to the aforesaid normal movements, automaticfrictionally acting means for operating the feeding device, and meansfor limiting the extent of movement of the feeding device.

32. In a relieving lathe, the combination of means for holding androtating a cutter, a tool holder, means for moving the tool holdertoward and away from the cutter in timed relation to the rotationthereof, a device for giving the tool holder` a feeding movementsupplemental to the aforesaid normal movements, automatic frictionallyacting means for operating the feeding device, and an adjustable devicefor stopping the feeding device after movement to a predeterminedextent.

33. In a relieving lathe, the combination of means for .holding androtating a cutter, a tool holder, means for moving the tool holdertoward and away from the cutter in timed relation to the rotationthereof, a device for giving thei tool holder a feeding movementsupplemental to the aforesaid normal movements, automatic frictionallyacting means for operating the feeding device, a

device for stopping the feeding device after movement to a predeterminedextent, and means for rendering the said stopping de-` vice inoperativewhereby the feeding device may be moved indefinitely in eitherdirection.

34. In a relieving lathe, the combination of means for holding androtating a cutter, a tool holder, means for moving the tool holdertoward and away from the cutter in timed relation to the rotationthereof, a device for giving the tool holder a feeding movementsupplemental yto the aforesaid normal movements, automatic frictionallyacting means for operating the feeding der' vice, a device for stoppingthe feeding device after movementto a predetermined extent, a device forstopping the operation of the automatic operating means, and a devicefor rendering the said stopping device inoperative, whereby the feedingdevice may be manually moved indefinitely in either direction.

35. In a relieving lathe, the combination of means for holding androtating a cutter. a tool holder, means for moving the tool holdertoward and away from the cutter in timed relation to the rotationthereof, a device for giving the tool holder a feeding of the automaticoperating means and rendering the said stopping device inoperativewhereby the feeding device may be manually moved indefinitely in eitherdirection.

36. In a relieving lathe, the combination of means for holding androtating a cutter, a tool holder, means for moving the tool holdertoward and away from the cutter in timed relation to the rotationthereof and independently of any movement of the tool along the face ofthe cutter, a device for giving the tool holder a feeding movementsupplemental to the aforesaid normal movements, and automatic meansoperable in timed relation with the cutter rotation and comprising apawl and ratchet wheel for intermittently operating the feeding device.

37. In a relieving lathe, the combination of means for holding androtating a cutter, a tool holder, means for moving the tool holdertoward and away from the cutter in timed relation tothe rotation thereofand independently of any movement of the tool along the face of thecutter, a'device for giving the tool holder a feeding movementsupplementall to the aforesaid normal movements, automatic meansoperable in timed relation with the cutter rotation and `comprising apawl and ratchet wheel for intermittently operating the feeding device,and a manually controllable device supplemental to-the said automaticmeans for rendering the said means inoperative. l

38. Iny a relieving lathe, the combination of means for holding androtating a cutter, a tool holder, means for moving the tool heldertoward and away from the cutter in timed relation to the rotationthereof, a device for giving the tool holder a feeding movementsupplemental to the aforesaid normal movements, automatic means foroperating the feeding device, and a manually controllable clutchinterposed between the automatic operating means and the feeding device.

39. In a relieving lathe, the combination of means for holding androtating a cutter, a tool holder, means `for moving the tool holdertoward and away from the cutter in timed relation to therotationthereof, a device for giving the tool holder a feeding movementsupplemental to the aforesaid normal movements, means for automaticallyoperating the feeding device, and means for manually operating thefeeding device inV of means for holding and rotating a cutter, a toolholder, means for moving the tool holder toward and awa from the cutter-in timed relation to the rotation thereof, a device for giving the toolholder a feeding movement supplemental to the aforesaid normalmovements, means comprising a ratchet wheel and a pawl for automaticallyoperating the feeding device, and means for manually Operating thefeedin device in either direction While the pavvl is in operativerelation with the wheel.

41'. In a relieving lathe, the combination of means for holding androtating a cutter, a horizontal tool carrying slide, a turntable havingseparated ways supporting the slide, a slide actuating device mountedindependently of the turntable in ways formed on the bottom of theslide, means engaging the slide and the actuating device for relativelyadjusting them, and a reciprocating means operable for all positions ofthe turntable and comprising an elementpositioned beneath the actuatingdevice and directly engaging therewith.

42. In a relieving lathe, the combination of means for holding androtating a cutter,

a horizontal tool carrying slide, a horizontal turntable supporting theslide, a slide actuating device normally movable therewith,

means engaging the slide and the actuating` device for relativelyadjusting them, a reciprocating means engaging the actuating device andoperable for all positions of the turntable, and means movement with theslide for operating the adjusting means while the slide and actuatingdevice are rin motion.

43. In a relieving lathe, the combination of means for holding androtating a cutter, a horizontal turntable, a horizontal tool carryingslide on the turntable, means operable for all positions of theturntable for moving the slide toward and away from the cutter in timedrelation to the rotation thereof, and automatic means for causing theforward limit of the movements toward the cutter to be advanced.

44:. In a relieving lathe, the combination of means for holding androtating a cutter, a horizontalturntable, a horizontal tool carryingslide on the turntable, means operable for all positions of theturntable for moving the slide toward and away from the cutter in timedrelation to the rotation thereof, and automatic means for causing theforwar limit of the movements toward the cutter to be intermittentlyadvanced.

45. In a relieving lathe, the combination of -means for holding androtatinff a cutter, a horizontal turntable, a horizonta tool carryingslide on' the turntable. means operable for all positions of theturntable for moving the slide toward and away from the cutter fixedagainst bodily4 rying slide on the turntable, means operable for allpositions of the turntable for moving the slide toward and away from thecutter in timed .relation to the rotation thereof, and automatic feedingmeans for the slide supplemental to the said moving means.

47. In a relieving lathe, the combination of means for holding androtating a cutter,`

a horizontal tool carrying slide, a turntable supporting the slide, aslide actuating device normall i movable therewith, means engaging theslide and the actuating device for relatively adjusting them, areciprocating means engaging the actuating device and operable for allpositions of the turntable, and automatic means connected with theadjusting means for operating it irrespectively of the position of theturntable.

48. In a relieving lathe, the combination of means for holding androtating a cutter, a horizontal turntable, a horizontal tool carryingslide on the turntable movable toward and away from the cutter in timedrelation to the rotation thereof, an element mounted for movement aboutthe axis of the turntable, and a feeding device adapted to be Vactuatedby the said element irrespectively of the position of the turntable.

'49. In a relieving lathe, the combination of means for holding androtating a cutter, a horizontal turntable, a horizontal tool carryingslide on the turntable, means operaable for all positions of theturntable for moving the slide toward and away from the cutter in timedrelation to the rotation thereof, an element supplemental to the saidmoving means mounted for movement about the axis of the turntable, and afeeding de vice adapted to be actuated by the said clementirrespectively of the position of the turntable.

50. In a relieving lathe, the combination of means for holding androtating a cutter, a horizontal turntable, a `horizontal tool carryingslide on the turntable movable toward and away from the cutter in timedrelation to the rotation thereof, an clement mounted for oscillationabout a vertical axis, and a feeding device adapted to be actuated bythe said element irrespectively of the position of the turntable.

51. In a relieving lathe, the combination of means for holding androtating a. cutter, a horizontal turntable, a horizontal tool carryingslide on the turntable, means operica;

able for all positions of the turntable for moving the slide toward andaway from the cutter ir. timed relation to the rotation thereof, anelement mounted for oscillation about the axis of the turntable, and afeeding device adapted to be actuated by the said element irrespectivelyof the position of the turntable.

In a relieving lathe, the combination of means for holding and rotatinga cutter,

a horizontal turntable, a horizontal tool car-v rying slide on theturntable, means operable for all positions of the turntable for movingthe slide toward and away from the cutter in timed relation to therotation thereof, an annular toothed gear mounted for movement about theaxis of the turntable and exposed throughout a largeportion of itsperiphery, a driving gear meshing with the annular gear and fixedaga-inst bodilymovement with the turntable as it nieves angularly, and afeeding device.

adapted to be actuated by the annular gear irrespectively of theposition of the turn? table.

.54. In a relieving lathe, the combination of means for holding androtating a cutter, a horizontal turntable, a horizontal tool carryingslide on the turntable, means operable for all positions of theturntable for moving the slide toward and away from the cutter in timedrelation to the rota-tion thereof, an annular toothed gear mounted formovement about the axis of the turntable, and a' feeding devicecomprising a gear meshing with the annular gear and adapted to beactuated thereby irrespectively of the position of the turntable.

55. In a relieving lathe, the combination of means for holding androtating a cutter, a horizontal turntable, a horizontal tool car- Y.rying slide on the turntable, means operable for all positions of theturntable for moving the slide toward and away from the cutter in timedrelation to the rotation thereof, an annular toothed gear mounted formovement about the axis of the turntable and exposed throughout a largeportion of its periphery, a driving gear meshing with the annular gearand fixed against bodily movement with the turntable as it movesangularly, and a feeding device comprising a gear meshing with theannular gear and adapted to be actuated thereby irrespectively of theposition of the turntable.

56. In a relieving lathe, the combination of means including a livespindle for holding and rotating a cutter, driving means for thespindle, including a drive shaft, two differently speeded powerconnections between the shaft and the spindle and a clutch .wherebyeither of the connections may be made operative and the otherinoperative at the option of the operator, a tool holder, and meansoperated by the drive shaft independently of the spindle for moving thetool holder toward and away from the cutter in timed relation to therotation thereof.

57. In a relieving lathe, the combination of means including a livespindle for holding and rotating a cutter, driving means for the spindleincluding a drive shaft, two differently speeded power connectionsbetween the shaft and the spindle and a clutch'whereby either of thesaid connections may be made v operative and the other inoperative atthe option of the operator, a tool holder,"and means operated bythedrive shaft independ-` ently of the spindle andincluding changespeedmechanism for moving the tool holder toward and away from the cutter.

58. In a relieving lathe, the combination of means including a livespindle for holding and rotating a cutter, driving means for the spindleincluding two differently speeded worm and wheel con-A nections betweenthe shaft and the spindle and a clutch lwhereby either of theconnections may be made operative and the other inoperative at theoption of the operator, *a tool holder, and means operated by the driveshaft independently of the spindle for moving the tool holder toward andaway from the cutter in timed relation to the rotation thereof.

59. In a relieving lathe, the combination of-means including a livespindle for holding and rotating a cutter, driving means for the spindleincluding a transverse drive shaft, twof differently speeded worm andwheel connections between the shaft and thev 'of abcd, a headstockprovided with means` for rotating a cutter, a tailstock supportpositioned vertically above and parallel to the bed with its center linein the same vertical plane as the centerline of the head stock, a

a transverse drive shaft,`

